* Pro-Russia rebels call victory in East Ukraine vote
* Top exporter Saudi Arabia would supply more oil if needed
* EU expands sanctions over Ukraine crisis
* Libya's oilfields, pipelines to reopen later Monday evening
(Rewrites throughout, updates prices, adds analyst commentary, changes byline, dateline, previous LONDON)
NEW YORK, May 12 (Reuters) - Crude oil prices rose on Monday as investors braced for a possible escalation in Ukraine's civil conflict and the European Union expanded sanctions to Russian individuals and Crimean companies.
Though it is unlikely the turmoil would lead to a disruption in energy supplies from Russia, top global oil exporter Saudi Arabia volunteered to supply more crude in the event of a shortage.
Pro-Moscow rebels claimed a resounding victory on Sunday in a referendum in eastern Ukraine, with some saying that meant independence and maybe eventual union with Russia as clashes broke out between separatists and troops.
The European Union agreed to impose sanctions on two Crimean companies and 13 more Russians and Ukrainians on Monday, although the measures still fall far short of Washington's sanctions against 17 companies passed in March and April.
"Although there are still no signs that there will be an interruption in oil supply from Russia due to the Ukrainian situation, the market remains concerned each time a new event evolves from the Ukraine," said Dominick Chirichella of Energy Management Institute in New York.
Brent crude was up 61 cents at $108.50 a barrel by 11:16 a.m. EDT (1516 GMT), while U.S. crude gained 83 cents to $100.82 a barrel.
Gains in Brent were capped as Libya announced its western oilfields and pipelines will reopen on Monday evening after protesters ended their blockade of key infrastructure, potentially raising Libyan output by 500,000 barrels per day.
U.S. crude futures remain in a trading range between $98 and $102 per barrel with expectations for a further draw at the Cushing, Oklahoma, delivery point proving supportive for the contract.
"The increased geopolitical risk has given (U.S. crude) a little support, but really it's around $100 and looking for its next driver," said Gene McGillian, analyst at Tradition Energy in Stamford, Connecticut.
"Officials in Libya are doing their regular song and dance about rebounding supply, but much of the risk of increased supply is already priced into Brent."
Investors kept an eye out for industrial production and retail sales data expected from China on Tuesday.
On Friday, China pledged to move ahead with a broad range of reforms to the country's capital markets in a bid to increase transparency, encourage more efficient capital allocation and increase openness to foreign investment.
Negotiators from Iran and the International Atomic Energy Agency met in Vienna, a day before talks resume between Tehran and six western nations over Iran's nuclear program.
The two sets of talks are separate but closely linked as both focus on fears that Iran may be covertly seeking the capability to develop nuclear weapons.
Any sign of progress towards a final resolution to the West's dispute with Tehran would pressure oil prices in anticipation of a ramp-up in Iranian oil exports.
(Additional reporting by Peg Mackey in London and Keith Wallis in Singapore; Editing by Keiron Henderson, David Evans and Marguerita Choy)